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IN SITU TEM STUDY ON THE R-PHASE TRANSFORMATION IN TiNi ALLOY 被引量:10
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作者 CHEN Qing WU Xingfang and C. J. Humphreys(Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083, China)(Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CBZ 3QZ, U. K.) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第3期157-163,共7页
The R-phase transformation process in selected TiNi alloys has been studied in great detail by using in situ TEM technique. The R-phase transformation was found to be a reversible thermoelastic displacive transformati... The R-phase transformation process in selected TiNi alloys has been studied in great detail by using in situ TEM technique. The R-phase transformation was found to be a reversible thermoelastic displacive transformation with a nucleation and growth process. The R-phase nucleates at the precipitate/matrix interface in aged specimens and grows by moving the coherent R/matrix interfaces. The stress field of Ti3Ni4 precipitates plays a much more important role in the formation of the R-phase than dislocations in aged TiNi alloy. The microstructure of the R-phase has also been studied. 展开更多
关键词 r-phase transformation TiNi alloy in situ TEM
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R-phase transformation of aged Ti-Ni shape memory alloy
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作者 宫长伟 王轶农 +1 位作者 杨大智 刘晓鹏 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第6期1237-1241,共5页
Ti-50.6Ni(molar fraction, %) shape memory alloy solution treated at 850℃ for 1h followed by ageing treatment at 450℃ for 3h was studied with differential scanning calorimetry(DSC), X-ray diffractometry(XR... Ti-50.6Ni(molar fraction, %) shape memory alloy solution treated at 850℃ for 1h followed by ageing treatment at 450℃ for 3h was studied with differential scanning calorimetry(DSC), X-ray diffractometry(XRD) and transmission electron microscopy(TEM). DSC measurement reveals two separate transformation peaks. XRD and TEM demonstrate that a three-stage transformation occurs. The Ti3Ni4 precipitates are coherent with the R-phase. The crystal structure of R-phase was analyzed by two diffraction patterns method. The diffraction patterns of R-phase were obtained in detail from the same region. 展开更多
关键词 TI-NI合金 形状记忆合金 R相转变 钛合金
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Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels
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作者 Yishuang Yu Jingxiao Zhao +3 位作者 Xuelin Wang Hui Guo Zhenjia Xie Chengjia Shang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期380-390,共11页
This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic analyses.The results show that ... This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic analyses.The results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without Co.Moreover,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to 0.6.The improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant pair.Furthermore,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant pair.These findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels. 展开更多
关键词 high-strength steel COBALT transformation kinetics CRYSTALLOGRAPHY impact toughness
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Soliton Solutions of a Coupled KdV System via Backlund Transformation
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作者 CAO Xifang WU Yiheng +2 位作者 LU Yi XU Wenjing XIA Yutong 《应用数学》 北大核心 2025年第1期211-216,共6页
In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation ... In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions. 展开更多
关键词 KdV equation Coupled KdV system B¨acklund transformation SOLITON
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Xiamen after 20 Years of Ecological Transformation
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作者 ZACHARY G.LUNDQUIST 《China Today》 2025年第1期66-68,共3页
The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China... The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean city.TWENTY years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian Province.Unfortunately,due to the fact that I was in a rush,I did not have the chance to see the whole city.My memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this place.Twenty years went by until I was able to return to this city again.After emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and vibrant.What exactly had given this city such vitality? 展开更多
关键词 ECOLOGICAL XIAMEN transformation
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Evidence-Based Practice of Nutrition Management in Chronic Heart Failure Patients Based on Knowledge-to-Action Transformation Model
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作者 Jing Zhang Junjun Liu 《Open Journal of Applied Sciences》 2025年第2期400-410,共11页
Objective: To develop a best-evidence-based optimal nutrition management plan for patients with chronic heart failure, apply it in clinical practice, and evaluate its effectiveness. Methods: Use the KTA knowledge tran... Objective: To develop a best-evidence-based optimal nutrition management plan for patients with chronic heart failure, apply it in clinical practice, and evaluate its effectiveness. Methods: Use the KTA knowledge translation model to guide evidence-based practice in nutrition management, and compare the nutritional status, cardiac function status, quality of life, and quality review indicators of chronic heart failure patients before and after the application of evidence. Results: After the application of evidence, the nutritional status indicators (MNA-SF score, albumin, hemoglobin) of two groups of heart failure patients significantly increased compared to before the application of evidence, with statistically significant differences (p Conclusion: The KTA knowledge translation model provides methodological guidance for the implementation of evidence-based practice for heart failure patients. This evidence-based practice project is beneficial for improving the outcomes of malnutrition in chronic heart failure patients and is conducive to standardizing nursing pathways, thereby promoting the improvement of nursing quality. 展开更多
关键词 Chronic Heart Failure Knowledge transformation Mode Nutrition Management Evidence-Based Practice
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N-Fold Darboux Transformation and Various Solutions for the Coupled mKdV Equations
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作者 Chunmei Fang 《Journal of Applied Mathematics and Physics》 2025年第2期381-391,共11页
In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton s... In this paper, we get the N-fold Darboux transformation with multi-parameters for the coupled mKdV equations with the help of a guage transformation of the spectral problem. As an application, some new multi-soliton solutions and complexiton solutions are obtained from choosing the appropriate seed solution. All obtained solutions and N-fold Darboux transformations are expressed using the Vandermonde-like determinants. 展开更多
关键词 The N-fold Darboux transformation The Coupled mKdV Equations Multi-Soliton Solutions Complexiton Solutions
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National standard proposals on digital transformation approved
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《China Standardization》 2025年第1期8-8,共1页
The digital economy has become an important impetus of global economic growth. The rapid development of emerging and key technological fields, such as the new generation of information technology and biotechnology, ha... The digital economy has become an important impetus of global economic growth. The rapid development of emerging and key technological fields, such as the new generation of information technology and biotechnology, has put forward new requirements for standards development.However, the traditional mode of standards development relying on paper documents faces problems such as low efficiency, long cycle, and relatively low quality, which fails to meet current demands. 展开更多
关键词 transformation approved TECHNOLOGICAL
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Construction of Vocational Education Quality Evaluation Index System from the Perspective of Digital Transformation Based on the Analytic Hierarchy Process of Higher Vocational Colleges in Hainan Province,China
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作者 Limei Fu 《Journal of Contemporary Educational Research》 2025年第1期282-289,共8页
In the context of the digital transformation of vocational education,a quality evaluation index system has been constructed.Based on a questionnaire survey conducted among higher vocational colleges and enterprises in... In the context of the digital transformation of vocational education,a quality evaluation index system has been constructed.Based on a questionnaire survey conducted among higher vocational colleges and enterprises in Hainan Province,it has been found that the quality of vocational education generally depends on the talent training program and professional construction at the macro level.At the meso level,the teacher level and teaching environment are critical,while at the micro level,the evaluation of talent training quality cannot be underestimated.Strategies for quality improvement in vocational education are proposed from the perspectives of talent training programs,major construction,teacher development,teaching environment,and talent training quality,all under the lens of digital transformation. 展开更多
关键词 Digital transformation Vocational education Evaluation index system
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A Study on the Digital Transformation of Higher Education in Egypt
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作者 Gang Hu Ruonan Cao 《Journal of Contemporary Educational Research》 2025年第2期101-105,共5页
With the advancement of information technology,the digital transformation of higher education has become a global trend in educational reform.Egypt has propelled the modernization of its higher education system throug... With the advancement of information technology,the digital transformation of higher education has become a global trend in educational reform.Egypt has propelled the modernization of its higher education system through digital means,focusing on enhancing teachers’digital teaching capabilities,improving course quality,and establishing a policy environment that supports digital instruction.The driving forces behind Egypt’s transformation include meeting the demand for skilled talent due to economic reforms,participating in internationalization processes,and the impetus provided by public diplomacy.By introducing high-quality international resources,deepening scientific research collaboration,and applying digital technologies,Egypt has effectively alleviated issues of resource insufficiency and uneven development,thereby enhancing its capacity for higher education quality assurance.Egypt’s practice demonstrates that digitalization is a key pathway for developing countries to improve the quality of higher education,providing valuable insights for constructing sustainable models of higher education development. 展开更多
关键词 Higher education Public diplomacy Digital transformation
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Digitalization Empowers Higher Education Teaching Management-Reform and Innovation,Shaping and Transformation,Role and Inspiration,Challenges and Countermeasures
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作者 Ce Zhang Peng Liu +2 位作者 Xiaoying Liu Meng Wei Xuejie Zhao 《计算机教育》 2025年第3期10-23,共14页
The combination and application of information technology and higher education have led to changes in the form and mode of teaching management in higher education,promoting the continuous deepening of digital transfor... The combination and application of information technology and higher education have led to changes in the form and mode of teaching management in higher education,promoting the continuous deepening of digital transformation in higher education.This paper discusses higher education management innovation triggered by digital technology and the new appearance of digital university governance,digital evaluation management,and internal governance of higher education.From the perspective of forging new forms,models,and paths of digital management through digital technology,this paper focuses on analyzing the reshaping of management systems by digitalization in higher education.The promotion and inspiration of digitalization on management system reform are provided,including typical features brought about,new paths opened up,and new advantages shaped.It is emphasized that the establishment of digital management system needs to rely on the systematic integration of multiple aspects.Finally,the challenges and solutions faced by the digital management system are deeply analyzed from the aspects of collaborative management and services,management process interoperability,evaluation and trust protection,and personnel digital literacy.Digital technology drives the transformation of higher education management system,resulting in new forms,models,paths,and methods of networked and digital management based on intelligent analysis and processing of educational and teaching data and promoting higher education management toward digital governance.The comprehensive establishment of a digital management system will unleash strong potential for universities to better fulfill their functions,and the high-quality development of higher education will be more solid and powerful. 展开更多
关键词 Higher education Digital transformation Management system Digital management
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ESG rating and transformation upgrading of enterprises:An empirical test based on the heterogeneity of listed A-share enterprises
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作者 WEI Yu-xin LI Peng-yu +1 位作者 LI Yan CHEN Xi-meng 《Ecological Economy》 2025年第1期48-65,共18页
ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning ... ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning from 2019 to 2022,coupled with measures of corporate transformation and upgrading,this study introduces green innovation as a mediating variable to dissect the impact of ESG ratings on corporate transformation and upgrading.The key findings of this research are as follows:(1)ESG ratings positively influence corporate transformation and upgrading,a conclusion that retains robustness after a comprehensive series of tests and discussions on endogeneity.(2)Mechanism analysis reveals that ESG ratings foster corporate transformation and upgrading by enhancing corporate green innovation.(3)In comparison with other industries,the influence of ESG ratings on corporate transformation and upgrading is notably more pronounced among heavily polluting industries among listed companies in China.Additionally,ESG ratings exhibit a more significant promotional effect on non-state-owned enterprises compared to state-owned enterprises.Larger enterprises play a more substantial role in transformation and upgrading than small and medium-sized enterprises.The promotional effect of ESG ratings is more evident in enterprises with poor information disclosure quality.Furthermore,as media attention increases,so does the impact of ESG ratings on corporate transformation.This study offers valuable policy insights from the ESG rating perspective,aiming to propel corporate transformation and upgrading,thereby contributing to economic high-quality and sustainable development. 展开更多
关键词 ESG rating enterprise transformation and upgrading heterogeneity analysis
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Development of an Agrobacterium tumefaciens-mediated transformation system for somatic embryos and transcriptome analysis of LcMYB1's inhibitory effect on somatic embryogenesis in Litchi chinensis
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作者 Yaqi Qin Bo Zhang +6 位作者 Xueliang Luo Shiqian Wang Jiaxin Fu Zhike Zhang Yonghua Qin Jietang Zhao Guibing Hu 《Journal of Integrative Agriculture》 2025年第2期594-609,共16页
Litchi has great economic significance as a global fruit crop.However,the advancement of litchi functional genomics has encountered substantial obstacles due to its recalcitrance to stable transformation.Here,we prese... Litchi has great economic significance as a global fruit crop.However,the advancement of litchi functional genomics has encountered substantial obstacles due to its recalcitrance to stable transformation.Here,we present an efficacious Agrobacterium tumefaciens-mediated transformation system in somatic embryos of‘Heiye'litchi.This system was developed through the optimization of key variables encompassing explant selection,A.tumefaciens strain delineation,bacterium concentration,infection duration,and infection methodology.The subsequent validation of the transformation technique in litchi was realized through the ectopic expression of LcMYB1,resulting in the generation of transgenic calli.However,the differentiation of transgenic calli into somatic embryos encountered substantial challenges.To delineate the intricate molecular underpinnings of LcMYB1's inhibitory role in somatic embryo induction,a comprehensive transcriptome analysis was conducted that encompassed embryogenic calli(C),globular embryos(G),and transgenic calli(TC).A total of 1,166 common differentially expressed genes(DEGs)were identified between C-vs.-G and C-vs.-TC.Gene Ontology(GO)annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis revealed that these common DEGs were mostly related to plant hormone signal transduction pathways.Furthermore,RT-qPCR corroborated the pronounced down-regulation of numerous genes that are associated with somatic embryo induction within the transgenic calli.The development of this transformation system provides valuable support for functional genomics research in litchi. 展开更多
关键词 Litchi chinensis A.tumefaciens transformation LcMYB1 somatic embryo
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The Road of“Coal to Gas”in the Transformation of Energy Structure—Current Status and Strategic Suggestions for Foshan City’s Policy Implementation
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作者 Wanyi Chen Yifeng Huang 《Journal of Electronic Research and Application》 2025年第1期74-80,共7页
Under the guidance of national policies,the“coal to gas”project has become one of the important measures to promote the transformation of energy structure in China.Foshan,an important industrial town in Guangdong pr... Under the guidance of national policies,the“coal to gas”project has become one of the important measures to promote the transformation of energy structure in China.Foshan,an important industrial town in Guangdong province,the implementation of the“coal to gas”policy has demonstrated significance for the optimization of the national energy structure.Through the analysis of the change in Foshan’s energy consumption structure and the implementation of the policy,this paper found that there were some challenges in the policy implementation process,such as high economic cost,lagging infrastructure,low social acceptance,and lack of technical personnel.To address this,suggestions are put forward,including increasing financial subsidies,improving laws and regulations,promoting technological innovation,and encouraging social inclusion policies.These recommendations aim to provide guidance and reference for the remaining“coal to gas”projects and the development of clean energy. 展开更多
关键词 Coal to gas Energy structure transformation Foshan City Clean energy
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Streamlined Agrobacterium rhizogenes-mediated hairy root transformation for efficient CRISPR/Cas9-based gene editing evaluation in diverse Citrullus cultivars
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作者 Yong Zhao Hongju Zhu +7 位作者 Xuqiang Lu Muhammad Anees Nan He Dongdong Yang Zihao Chen Zonglie Hong Junhong Zhang Wenge Liu 《Horticultural Plant Journal》 2025年第2期816-826,共11页
The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficie... The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficiency of gene editing varies among sgRNAs,emphasizing the need to meticulously select target sites,especially in the context of Citrullus lanatus,a species notorious for its challenging and inefficient generation of transgenic plants through stable transformation.This study employed an Agrobacterium rhizogenes-mediated hairy root method to assess effective target sites for gene editing of ClCIPK17 across various Citrullus species.Hairy roots were successfully induced in different plant tissues at diverse growth stages of Citrullus lanatus,Citrullus mucosospermus,and Citrullus amarus.Employing a vector with two sgRNAs(sgRNA1 and sgRNA5)positioned within conserved regions of exon 1 and exon 5 of ClCIPK17 in the CRISPR/Cas9 system,targeted mutations were detected in 90.9%of accessions across the four Citrullus species.Notably,73.94%of all examined hairy roots exhibited mutations at the sgRNA1 site,while the sgRNA5 site showed no mutations.Among the 31 different mutation types identified at the sgRNA1 site,base deletion was the most prevalent.Using the sgRNA1 site of ClCIPK17,stable transgenic watermelon buds were obtained from explants,and the targeted mutations of the sgRNA1 site were confirmed.These findings underscore the viability of the hairy root transformation system in assessing the editing efficiency of sgRNA targets in diverse Citrullus species. 展开更多
关键词 Citrullus lanatus sgRNAs Agrobacterium rhizogenes Hairy root transformation CRISPR/Cas9
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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 OCEAN RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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基于Transformer模型的时序数据预测方法综述 被引量:1
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作者 孟祥福 石皓源 《计算机科学与探索》 北大核心 2025年第1期45-64,共20页
时序数据预测(TSF)是指通过分析历史数据的趋势性、季节性等潜在信息,预测未来时间点或时间段的数值和趋势。时序数据由传感器生成,在金融、医疗、能源、交通、气象等众多领域都发挥着重要作用。随着物联网传感器的发展,海量的时序数据... 时序数据预测(TSF)是指通过分析历史数据的趋势性、季节性等潜在信息,预测未来时间点或时间段的数值和趋势。时序数据由传感器生成,在金融、医疗、能源、交通、气象等众多领域都发挥着重要作用。随着物联网传感器的发展,海量的时序数据难以使用传统的机器学习解决,而Transformer在自然语言处理和计算机视觉等领域的诸多任务表现优秀,学者们利用Transformer模型有效捕获长期依赖关系,使得时序数据预测任务取得了飞速发展。综述了基于Transformer模型的时序数据预测方法,按时间梳理了时序数据预测的发展进程,系统介绍了时序数据预处理过程和方法,介绍了常用的时序预测评价指标和数据集。以算法框架为研究内容系统阐述了基于Transformer的各类模型在TSF任务中的应用方法和工作原理。通过实验对比了各个模型的性能、优点和局限性,并对实验结果展开了分析与讨论。结合Transformer模型在时序数据预测任务中现有工作存在的挑战提出了该方向未来发展趋势。 展开更多
关键词 深度学习 时序数据预测 数据预处理 transformer模型
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基于CNN-BiLSTM-Transformer的舰船中压直流全电推进系统故障诊断设计
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作者 张建良 韩涛 季瑞松 《实验技术与管理》 北大核心 2025年第1期11-18,共8页
针对舰船中压直流全电推进系统结构复杂度高、单元耦合性强、运行环境多变等特点造成的故障诊断准确性低和实时性差等问题,开展了基于CNN-BiLSTM-Transformer的故障诊断设计。首先,基于卷积神经网络CNN构建单点特征级联网络,开展单一时... 针对舰船中压直流全电推进系统结构复杂度高、单元耦合性强、运行环境多变等特点造成的故障诊断准确性低和实时性差等问题,开展了基于CNN-BiLSTM-Transformer的故障诊断设计。首先,基于卷积神经网络CNN构建单点特征级联网络,开展单一时刻下故障信号空间特征的深入提取,以提升故障特征提取的有效性;其次,以双向长短期记忆网络BiLSTM为核心设计多点特征依赖网络,利用门控机制和双向时序学习机制,实现故障信号在多个时刻之间特征依赖关系的有效学习,以提升故障诊断的准确性;然后,以Transformer为核心建立序列特征并行处理网络,通过自注意力机制实现对故障特征上下文关系的精确刻画,进而利用多头注意力机制实现特征序列的并行处理,以提升故障诊断的实时性;最后,设计舰船中压直流全电推进系统故障诊断实验方案,并开展不同故障模式下的诊断性能评估。该文方法在多种故障模式下诊断准确率和实时性均优于现有的主流故障诊断方法,有助于为舰船中压直流全电推进系统的安全运行提供更有力的技术保障。 展开更多
关键词 舰船 中压直流 全电推进系统 故障诊断 transformER
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融合CNN与Transformer的遥感影像道路信息提取
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作者 曲海成 王莹 +1 位作者 刘腊梅 郝明 《自然资源遥感》 北大核心 2025年第1期38-45,共8页
利用高分辨率遥感影像进行道路信息提取时,深度神经网络很难同时学习影像全局上下文信息和边缘细节信息,为此,该文提出了一种同时学习全局语义信息和局部空间细节的级联神经网络。首先将输入的特征图分别送入到双分支编码器卷积神经网络... 利用高分辨率遥感影像进行道路信息提取时,深度神经网络很难同时学习影像全局上下文信息和边缘细节信息,为此,该文提出了一种同时学习全局语义信息和局部空间细节的级联神经网络。首先将输入的特征图分别送入到双分支编码器卷积神经网络(convolutional neural networks,CNN)和Transformer中,然后,采用了双分支融合模块(shuffle attention dual branch fusion block,SA-DBF)来有效地结合这2个分支学习到的特征,从而实现全局信息与局部信息的融合。其中,双分支融合模块通过细粒度交互对这2个分支的特征进行建模,同时利用多重注意力机制充分提取特征图的通道和空间信息,并抑制掉无效的噪声信息。在公共数据集Massachusetts道路数据集上对模型进行测试,准确率(overall accuracy,OA)、交并比(intersection over union,IoU)和F 1等评价指标分别达到98.04%,88.03%和65.13%;与主流方法U-Net和TransRoadNet等进行比较,IoU分别提升了2.01个百分点和1.42个百分点,实验结果表明所提出的方法优于其他的比较方法,能够有效提高道路分割的精确度。 展开更多
关键词 级联神经网络 transformER 特征融合 注意力机制
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